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1.
根据发现于辽宁省西部下白垩统九佛堂组的一近乎完整的梳齿颌翼龙类下颌,确立了一新属新种:短颌辽西翼龙Liaoxipterus brachyognathus gen.et sp.nov.短颌辽西翼龙以它前部扩张的下颌缝合部,左右第四齿槽间的距离最宽等特征不同于发现于辽西及其周边地区任何具有头骨保存的翼龙类,基于其扁宽的下颌吻端,牙齿大小分异小及短的下颌缝合部,把它归入梳齿翼龙类,短颌辽西翼龙以其较少的牙齿数目区别于其他梳齿颌翼龙,  相似文献   

2.
吕君昌 《地球学报》2015,36(3):362-366
在翼龙类不同的类群中其摄食行为是不同的,从其牙齿形状以及石化的胃容物来判断,其摄食行为包括食鱼类、食昆虫类、滤食水中小的水生生物、食螃蟹和蜗牛等带壳的动物,以及食水果类等。由于生存的需要,它们占据不同的生态灶,决定了其食物来源的不同。本文描述了宽颌辽西翼龙一件几乎完整、保存完好的与下颌在一起的舌器化石标本,并且它与现生蜥蜴类变色龙的舌器对比。它长的舌突与运用其舌的外翻来摄取食物的现生蜥蜴类-变色龙相类似,从而暗示了辽西翼龙可能具有类似的、用舌获取食物的行为,加上其独特的牙齿形态,进一步提出辽西翼龙是食昆虫类而不是食鱼的翼龙。  相似文献   

3.
姬书安  张笠夫 《地学前缘》2020,27(6):365-370
发现于内蒙古鄂托克旗召稍早白垩世罗汉洞组的一件不完整翼龙类下颌标本,以下颌愈合部长且平直、齿骨侧嵴发育、近圆形齿窝沿侧嵴之上的齿骨侧面上半部分自前向后呈直线排列、齿窝直径(2~2.5 mm)前后变化较小、相邻齿窝的间距约为齿窝直径的一半、下颌牙齿密度为3枚/cm等特征,可归入梳颌翼龙科(Ctenochasmatidae),且代表一新属种——郝氏鄂托克翼龙Otogopterus haoae gen.et sp.nov.。该化石是继鄂托克旗新召准噶尔翼龙科的平颌鄂尔多斯翼龙Ordosipterus planignathus之后在内蒙古鄂尔多斯地区发现的第2件确切翼龙类材料,丰富了这一地区早白垩世脊椎动物群的组成。该翼龙也是继甘肃庆阳环河翼龙Huanhepterus quingyangensis之后在鄂尔多斯盆地发现的第2种梳颌翼龙科化石,进一步扩大了鄂尔多斯盆地梳颌翼龙科的地理分布范围,同时表明鄂尔多斯盆地是继辽宁西部之后梳颌翼龙科在中国的又一重要分布区。  相似文献   

4.
本文总结了古神翼龙类的特征,尤其是对中国发现的没有牙齿的翼龙类(包括古神翼龙类、朝阳翼龙类及神龙翼龙类)进行系统总结。通过对比,把中国的古神翼龙类建立两个新的亚科:中国翼龙亚科及华夏翼龙亚科。从古神翼龙类头骨形态变化来看,其演化趋势是头骨由低长向短高变化,这一变化的原因可能与其食性变化有关。根据在辽西凌源四合当九佛堂组发现的一几乎完整的化石骨架建立了中国翼龙新种:凌源中国翼龙(新种),它具有以下特征:鼻眶前孔的长度与高度之比率为3.20;吻部指数为3.03;股骨与胫骨长度之比率约为0.66以及第2翼指骨与第1翼指骨长度之比率为0.85。根据发现于辽西朝阳九佛堂组的另一个体较小的古神翼龙类化石骨架,建立华夏翼龙属一新种:返祖华夏翼龙(新种)。虽然它个体较小,但是它具有华夏翼龙类似的头骨脊,然而它的第2和第3翼指骨的后面具有原始喙嘴龙类翼龙的沟状结构,以区别于其它的华夏翼龙类。返祖华夏翼龙的翼指骨后部沟状结构的出现,应为返祖现象的体现。而这一现象,在翼手龙类中为首次报道。  相似文献   

5.
根据发现于辽西朝阳九佛堂组一具有部分头骨的不完整骨架,命名一新的帆翼龙--赵氏龙城翼龙(新属新种).头骨和牙齿形态显示龙城翼龙与宽齿帆翼龙的关系要比与其他翼龙的关系密切,龙城翼龙是目前辽西九佛堂组中发现的唯一的帆翼龙类.帆翼龙科原仅一属种,发现于英国早白垩世地层中,辽西早白垩世新帆翼龙的发现,不但扩大了其地理分布,也证明辽西是晚侏罗世至早白垩世翼龙辐射、分异的重要地区.这对研究翼龙的起源和演化有重要意义.  相似文献   

6.
吕君昌  袁崇喜 《地质学报》2005,79(4):443-443
根据一具有头骨和下颌保存的几乎完整骨架,建立古神翼龙类一新属新种:季氏华夏翼龙。华夏翼龙的头骨形态显示它处于中国翼龙和古神翼龙的过渡阶段。从华夏翼龙头骨的形态(低的头骨脊)看,显示了它与中国翼龙的关系要比与具有高的头骨脊的古神翼龙密切。中国翼龙相对低长的头骨显  相似文献   

7.
根据发现于辽宁省西部下白垩统义县组的一近乎完整翼龙骨架,确立了鸟掌龙类一新属新种:崔氏北方翼龙Boreopterus cuiae gen.et sp.nov.。崔氏北方翼龙以其数量多的牙齿,且前部的九对牙齿大于后部的牙齿,上下颌的第四对牙齿稍微大于第三对等特征不同于辽西及其周边地区所发现的任何具有头骨保存的翼龙类。总的来说,  相似文献   

8.
达尔文翼龙的发现及其意义   总被引:1,自引:0,他引:1       下载免费PDF全文
吕君昌 《地球学报》2010,31(2):129-136
达尔文翼龙为中等大小的翼龙类, 发现于辽西辽宁省建昌县玲珑塔中侏罗世髫髻山组, 是目前已知唯一由原始类群(非翼手龙类)向进步类群(翼手龙类)演化的过渡类型。它既具有原始类群的特征: 比如尾长, 多于20节尾椎椎体, 且尾椎椎体由极度加长的、纤细的前后关节突及脉弧所包裹, 构成一僵硬的尾部, 第五脚趾具有两个长的趾节; 又具有进步类群的特征: 比如头骨加长, 鼻孔和眶前孔愈合为一大的鼻眶前孔, 颈椎椎体长, 没有或者颈肋退化; 翼掌骨与肱骨的比率介于原始类群和进步类群之间。达尔文翼龙的发现具有重要意义, 它填补了由原始翼龙类向进步翼龙类演化的空白, 为生物宏观演化(模块演化)机制-即组成生物体的模块在短时间内共同演化提供例证。从达尔文翼龙的骨骼结构变化上看, 空中丰富的食物来源(比如飞行能力差的、带羽毛的恐龙、滑翔的哺乳动物、小的翼龙及昆虫等), 可能为导致翼龙头骨和颈部首先演化的原因之一。达尔文翼龙的发现, 有可能打破对翼龙类传统分为两大类的方法。  相似文献   

9.
姬书安  张立军  路芳 《地质学报》2023,97(6):1723-1740
中国辽宁西部早白垩世翼龙类化石非常丰富,其上部的九佛堂组翼龙类组合以含有丰富的无齿的古神翼龙科、朝阳翼龙科等进步类型而与下部的义县组翼龙类组合相区别。本文描述了辽宁西部建昌盆地九佛堂组一新的大型翼龙类化石,其以上下颌无齿、吻端指数为3.7、前颌骨背支细长且封闭鼻眶前孔背缘、很大的鼻眶前孔后端超过上下颌关节位置、轭骨的上颌骨突基部宽大而应被归入朝阳翼龙科(Chaoyangopteridae)神州翼龙属(Shenzhoupterus)。其以较大的体形(翼展2.05 m)、平直的上下颌咬合面、轭骨的眶后骨突较泪骨突长且基部略宽、第4~7颈椎长度依次减小等特征,区别于朝阳神州翼龙(Shenzhoupterus chaoyangensis),而被命名为三亚神州翼龙(新种)(Shenzhoupterus sanyainus sp. nov.)。这是辽宁西部早白垩世翼展最大且不具牙齿的翼龙类属种,它的发现丰富了九佛堂组翼龙类组合内容,对认识朝阳翼龙科的骨骼形态与生态习性亦具有积极意义。  相似文献   

10.
根据中国浙江东阳上白垩统金华组发现的4个翼龙足迹,建立翼龙一新的遗迹种:东阳翼龙足迹。它具有以下特征:手迹的第Ⅱ和第Ⅲ指夹角为29°,第Ⅰ指和第Ⅱ指的夹角为52°;足迹的长与宽的比率为0.17,除了翼龙足迹外,在同一层位中还发现有蜥脚类、鸟脚类、兽脚类、帯蹼和不具蹼的鸟类足迹。这些足迹化石的发现,为研究该地区的古生态环境及以后动物的骨骼化石,尤其是翼龙骨骼化石提供了重要依据。  相似文献   

11.
A new Sordes-like pterosaur Jianchangopterus zhaoianus gen. et sp. nov. is erected based on a almost complete skeleton with skull preserved. It is characterized by the following characters: seven and six pairs of upper jaw and lower jaw teeth respectively; the development of a recess on maxilla; the evenness of the dental margin in lateral view; a distinct central ridge along dorsal surface of the mandibular symphysis; wing phalanx 4 with strongly curved shaft approximately 96% the length of the wing phalanx 1. The discovery of a Sordes-like pterosaur Jianchangopterus, and other taxa from the same formation indicates that pterosaurs reached great diversities during the Middle to Upper Jurassic period.  相似文献   

12.
Based on a nearly complete lower jaw from the Early Cretaceous of Liaoning Province, a new ctenochasmatid pterosaur: Liaoxipterus brachyognathus gen, et sp. nov. is erected. Liaoxipterus brachyognathus is different from any known pterosaurs with skulls preserved from western Liaoning Province and its peripheral areas in that the anterior part of the mandibular symphysis is expanded, being widest between the fourth alveolus of each side. Liaoxipterus brachyognathus is assigned to Ctenochasmatidae based on the following characters: the rounded anterior end of the lower jaw is spatulated and dorsoventrally flattened and marked heterodonty in the dentition is absent. It differs from other ctenochasmatid pterosaurs in having relatively small number of teeth. Liaoxipterus is distinguished from some ornithocheirids, which have expanded anterior parts of the mandibular symphyses, such as Anhanguera piscator,Coloborhynchus robustus in which the teeth of the new pterosaur are not as variable.  相似文献   

13.
An isolated jaw fragment from the Late Cretaceous (Cenomanian) Cambridge Greensand Member of the West Melbury Marly Chalk Formation previously identified as a cestraciontid shark fin spine is referred to the pterosaur clade Azhdarchoidea on account of its lateral and occlusal foramina and edentuly. The specimen differs from the azhdarchoid Ornithostoma sedgwicki from the same deposit in having flat lateral surfaces and an acute dorsal/ventral apex. The specimen is similar in overall morphology to CAMSM B40085 from the same horizon and probably represents the corresponding jaw but from a different individual. Likely these specimens represent a new taxon but are considered too fragmentary to diagnose at present. A remarkably similar and distinctive morphology is found in unnamed pterosaur jaws from the Kem Kem Group (?Albian-Cenomanian) of Morocco, supporting the idea of faunal similarity between these two distant localities.  相似文献   

14.
A jaw bone attributed to the mid-Cretaceous azhdarchid pterosaur Alanqa saharica Ibrahim et al., 2010 is described. The new specimen from the Kem Kem beds of south eastern Morocco is unusual for the presence of expanded rostral bones that protrude above the occlusal surface of the jaws. The function of this unusual osteological modification is uncertain, but it is considered likely that it served a role in food processing, or perhaps jaw stability.  相似文献   

15.
16.
Pangupterus liui gen. et sp. nov. from the Jiufotang Formation of Sihedang, Lingyuan City, Liaoning Province is erected based on a nearly complete lower jaw. It is characterized by having a total of 36 slender curved teeth with sharp tips, forming a distinct fish-grabbing mechanism; the teeth are well-spaced and are circular in section; the length ratio of the mandibular symphysis to the whole jaw is 20%; and the ratio of the tooth root width to tooth length is 12%. Toothed pterosaurs make up about 56.3% of the pterosaur assemblage from the Jiufotang Formation, which indicates that toothed forms played a key role in the ecosystem.  相似文献   

17.
New Azhdarchid Pterosaur from the Early Cretaceous of Western Liaoning   总被引:5,自引:0,他引:5  
A nearly complete skeleton with a lower jaw of pterosaur from the Early Cretaceous of western Liaoning is described and assigned to a new genus, Eoazhdarcho gen. nov.. The new genus is characterized by a relatively small size,the ratio of the length to width of the middle series cervical vertebrae approximately 3.5 and the ratio of humeral length to femoral length approximately 0.96. The humerus of Eoazhdarcho shows great resemblances to that of previously described Azhdarchidae, so it is assigned to the family Azhdarchidae.  相似文献   

18.
Based on a new nearly naturally preserved skull and four cervical vertebrae of the pterosaur Feilongus sp. from the lower Cretaceous Jiufotang Formation of Beipiao, western Liaoning province, northeastern China, the diagnosis of Feilongus is amended. The revised diagnosis notes long, curved, needle-shaped teeth that are confined to the jaw far anterior to the nasoantorbital fenestra; posterior teeth that are slightly smaller than the anterior teeth; cervical vertebrae elongated with a ratio of length to width greater than 5; tooth number of about 78; and two cranial sagittal crests.  相似文献   

19.
A re-examination of fossil material from the Late Cretaceous Cambridge Greensand Member (CGM) of the West Melbury Marly Chalk Formation revealed a number of new specimens of edentulous pterosaur jaw fragments previously identified as shark fin spines and fish jaws and accessioned under the epithet ‘cestraciontid finray’ and ‘jaws of fish’. These are now recognised as pterosaurian jaw tips and referred to Ornithostoma sedgwicki Seeley, 1891 and Azhdarchoidea indet. This material increases the diversity of edentulous pterosaurs from the CGM.The edentulous pterosaur Ornithostoma sedgwicki Seeley, 1891 from the Cretaceous Cambridge Greensand of eastern England is reviewed. The holotype specimen is confirmed as a fragment of a premaxilla/maxilla of a non-tapejarid azhdarchoid on account of the conspicuous curvature of the dorsal and occlusal margins posteriorly and the presence of small neural foramina on the lateral margins. Neural foramina are not seen on jaws of members of the Pteranodontia, a group to which O. sedgwicki was included previously. The referral of O. sedgwicki to Azhdarchoidea eliminates the single known Lower Cretaceous occurrence of Pteranodontidae, restricting the temporal range of this taxon to the Upper Cretaceous. Postcranial material referred to O. sedgwicki from the type horizon is regarded as indeterminate Pterosauria.  相似文献   

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